Feeding mechanism for sewing machines



Feb. 7, 3950 R. SCHULTHESS FOR SEWING MACHINES 2 Sheets-Sheet l FEEDINGMECHANISM Filed June 19, 1947 a W1; 12 w///////////' INVENTOR. RobertSchulthess WITNESS I ATTORNEY Feb. 7, 11956 R. SCHULTHESS 2,496,817

' FEEDING MECHANISM FOR SEWING MACHINES Filed June 19, 1947 2Sheets-Sheet 2 INVENTOR. w Roberf Sc/zuhh 983 ATTORNEY WITNESS PatentedFeb. 7, 1950 FEEDING MECHANISM FOR SEWING MACHINES Robert Schulthess,Zurich, Switzerland, assignor to The Singer Manuf beth, N. J., a corporaacturing Company,

tion of New Jersey Eliza- Application June 19, 1947, Serial No. 755,702

8 Claims.

This invention relates to feed'ng mechanism for sewing machines and moreparticularly to means for rendering the feeding mechanism ineffective tofeed the work by lowering the feeddog below the work-supporting surfaceof the machine, and subsequently maintaining it there, so that the workmay be shifted by hand for the purpose of darning, embroidering andsimilar operations.

The invention has as a primary object to provide an improved andsimplified feed throw-out device which may be actuated, at will, torender the feeding mechanism effective or ineffective, without the useof tools and without the necessity of manually locking the parts thereofin either of their adjusted positions.

Another object of the invention is to provide a feed throw-out devicewhich may be actuated by the simple turning of a suitable controlelement located in a position in which it is conveniently accessible tothe hand of the operator.

With the above and other objects in view, as will hereinafter appear,the invention comprises the devices, combinations and arrangements ofparts hereinafter set forth and illustrated in the accompanying drawingsof a preferred embodiment of the invention, from which the severalfeatures of the invention and the advantages attained thereby will bereadily understood by those skilled in the art.

In the drawings, Fig. l is a bottom view, partly in section, of aportion of a sewing machine embodying the present invention.

Fig. 2 is a transverse vertical section taken on the line 2-2 of Fig. 1,with the parts in position to effect a normal feeding operation.

Fig. 3 is a fragmentary sectional view similar to Fig. 2, but with thefeeding mechanism adjusted to an ineffective position in which thefeed-dog is maintained below the upper surface of the work-support.

Fig. 4 is a detail view of the improved means for connecting thefeed-lift rock-shaft with the feed-bar, whereby the feed-bar is adjustedto, and operated in, either of two vertically spaced positions, in thelower of which the feed-dog is maintained, at all times, below the uppersurface of the work-support, as illustrated in Fig. 3.

Fig. 5 is a sectional view taken on the line 5--5 of Fig. 4.

Figs. 6 and 'I are inside face views of the two link members whichconstitute the connection between the feed-lift rock-shaft and thefeedbar.

Referring more specifically to the drawings,

the invention is disclosed as embodied in a sew ing machine comprising abase I affording a work-support 2 including a throat-plate 3 havingslots, as 4, through which operate the serrated teeth of a feed-dog 5,secured upon a feed-bar 6. At its forward end, the feed-bar is pivotallycon nected, at 1, to a feed-advance rocker 8 forming a part of afeed-drive rock-shaft 9 journaled on suitable pintles, as Ill, in theframe I beneath the work-support. Also journaled on pintles, as H,carried by the machine frame, is a feed-lift rock-shaft l2 havingadjacent its forward end a feed-lift rock-arm [3. A rotary loop-takershaft l4 also is journaled beneath the work-support 2, in bearingsprovided by the machine frame, and carries a loop-taker which cooperateswith a suitable thread carrying needle in the formation of stitches.Inasmuch as the stitchforming mechanism forms no part of this invention,illustration and description thereof is deemed unnecessary. If desired,the stitch-forming mechanism may be constructed and operated asdisclosed in United States patent of Goosman, No. 2,063,841, Dec. 8,1936. The machine frame also may be constructed substantially as shownin that patent.

Oscillatory movements are given to the feeddrive rock-shaft 9 and thefeed-lift rock-shaft l2 by any suitable means such, for example, as thatdisclosed in said Goosman patent.

Vertical movements are transmitted from the feed-lift rock-arm l3 to thefeed-bar 6 by a link l5 pivotally connected, at its upper end, by ashoulder screw it to the rear end of the feedbar. Adjacent its lowerend, the link I5 is formed with an aperture a affording two verticallyspaced arcuate seats I) and 0 adapted alternately to receive and bearupon a stud I! carried by the feedlift rock-arm l3. The stud l1conveniently may consist of a shoulder screw having its threaded end 18screwed into the arm l3, its shoulder portion extending through theaperture a in the link [5 and its head l9 spaced from the link l5sufficiently to receive, between its head and the link iii, a secondlink 2!) later to be described. The link I5 is adapted to be turnedabout its pivot Hi to place either of said seats I) or 0 above and incontact with the Stud [1. A coil spring 2|, having its upper endconnected, at 22, to the feed-bar l5 and its lower end connected, at 23,to the machine frame, constantly urges the feedbar and the link l5downwardly to maintain the seat b or c which is above the stud 11 inpressure contact with the stud. When the seat I) is in contact with thestud [1, as shown in Figs.

2 and 4, the link l5, and consequently the feedbar 6, are shifted to theuppermost of two vertically spaced positions. In this position thefeed-bar and the feed-dog carried thereby are given the horizontal feedand return movements and the rising and falling movements common toconventional, four motioned feeding mechanisms and'the teeth or thefeed-dog are caused to be projected above the upper surface of thework-support, as shown in Fig. 2 to effect the usual feeding of thework.

When the link I5 is swung about its pivot- 46 to the position shown inFig. 3, the spring 2! draws the feed-bar 6 and the link lidownwardly andforces the [1. Thus the feed-bar and the feed-dog carried thereby areshifted to the lowermost of their two vertically spaced positions. Inthis position, when the feed-bar and feed-dog are raised to theirmaximum elevation by the feed-lift mechanism, the teeth of the feed-dogare maintained below theupper surface of' the work-support and thereforearemaintained out-of contact with the work as shownin full lines in Fig.3, thus permitting the work to be shifted by hand, for darning,embroide'ring and similar operations.

'From the foregoing it will be apparent'that the'link I5 transmitsvertical movements -to' the feed-bar and that the angular positionthereof determines whether the feeding mechanism shall be effective orineffective to feed the work.

"Manually operable means, readily accessible to' the operator, isprovidedfor shifting the'link [5 from one of its-operative positions tothe door. This means comprises a crank-shaft 24, journaled in a bearingbushing 25 held in the frame I'(Fig. 1); the'crank-shaft having, at itsouter end a hand grasp preferably in the form of a fluted hand wheel 26.At its inner end, the crankshaft 24 carries a crank-arm 21,'to'which ispivotallyconnected, by a shoulder screw 28, one end of a connectinglink'29; the other end of the link 29 being pivotally connected, by ashoulder screw 30, to the feed-bar lifting link l5.

When'the hand wheeli2li, crank-arm?! and link 29 are in the positionsshown in Fig. 2, the stud I1 is in engagementwith the seat I) in thelink il Sand the feed-bar is held in its uppermost'operative position.Rotation of the'hand wheel 26 in the direction indicated by the arrowsa:'in?'Figs. 1'-and 2, will move'the parts to the'positions shown in Fig.3, thereby'shifting the seat over the stud l1, whereupon'the spring 2!draws the feed-bar, feed-dog and link l5 downwardly and forces theseat 0into contact with the-stud I1. 'This movement causes'the feed-bar and.feed-do to 'be dropped to their lowermost operative positionsin whichthe feed-dog is maintained,-. at all times, below the supper surface ofthe work-support to permit manual manipulation of the work.

To hold the link [5 in its two positions'ofadjustment andto maintainthe'alignment 0f the seats band 0 with the'stud H, a second link 20,hereinbefore mentioned, is' pivotally mounted uponthe screw l6 betweenthe link l5 and the feed-bar 6 (Fig. 5). This link extends substantiallyparallel tothe link I5 and they' have their inner faces (shown in'Figs.6 and 7 in contact. As shown-most clearly in Fig. 5, the link 20 hasthreaded into 'it,one end of -a hollow stud 3!, havingia'bore32-in'which: is slidingly fitted the-head of a plunger 33. Azcoil spring34, interposed between the head-of the plunger- 33and'a screw35'threaded intothe'stud '3|,'.urges the seat 0 into contactwith thestud,

' versa. the opposite sides of the stud 11, thereby preverticallyspaced4 rounded outer end of the plunger outwardly beyond the inner face ofthe link 26 and causes it to enter either of two indentations 36 formedon the inner and adjacent face of the link l5 thereby to hold the link15 in either of its two positions of adjustment. Adjacent its lower endthe link 20 is formed with an elongated aperture 31 through which passesthe stud l7. This aperture is of sufficient length to permit shifting ofthe stud from the seat b to the seat c and vice The sidewalls of theaperture 37 engage venting the link 20 from swinging about its pivot l6.Thus the plunger 33 is held in position to enter the indentations 35 tohold the seats b and c in alignment with the stud l7.

'Fromthe-foregoing it will be apparent that thisinvention has provided afeeding mechanism which is adapted to operate in either of twovertically spaced positions, in the upper of which it effects normalfeeding of the 'work' and in the lower of which the feed-dog ismaintained wholly below the upper surface of the work-support-and,therefore, has no efiect'on'the work;

thereby permitting manual manipulation of the work.

It will also be apparent that the invention has provided simplifiedmeans for shifting the feeding mechanism from one position to theotherand that the shifting may be effected by the simple expedient ofturninga readily accessiblehand wheel" and without the use of tools andwithout the-necessity of locking =or unlockinganyparts.

Having thus set'forth the nature of the invention, what I claimhereinis:

1. In a sewing machine, a feed-advance rocker, a feed-lift rock-shaft, afeed-bar pivotally connected to said feed-advance rocker, an arm on saidfeed-lift rock-shaft, a stud carried'bysaid arm, a link connecting saidarm and said feedbar, said link having a pair of verticallyand'horizontally spaced'seats located above the axis of said. stud andadapted selectively to rest upon said stud to locate said feed-bar ineither of two positions and to transmit verticalmovements to saidfeed-bar in either of said positions; and means to effect relativehorizontal movement between said link and said stud to cause the stud tobe shifted from one of'said seats to the other.

2. In a sewingmachine, a, feed-advance rocker, a feed-lift rock-shaft, afeed-bar pivotally connected to said feed-advance rocker, an arm on saidfeed-lift rock-shaft, a stud carried by said arm, a pair of linksconnectingsaid arm and said feed-bar, one of said links having apair ofvertically spaced seats adapted selectively to receive said stud tolocate said feed-bar in either of two vertically spaced positions and totransmit verticalmovementsto said-feed-bar in either of said positions,the other of said links having guide walls engaging said stud andholding it insaidseats, means to effect relative movement between saidone of saidlinks and said stud to cause the stud to be shifted from oneof said seats to the other, and spring detent means. between said linksimpositively to restrain them against relative movement.

3. In a sewing machine, a feed-advance rocker, a feed-lift rock-shaft, afeed-bar pivotally connected to said feed-advance rocker, an arm' onsaid feed-lift rock-shaft,- a stud carried by said arm, a linkconnecting said: am andsaid feedbar, said link having a pair ofvertically spaced seats adapted selectively to receive said-studiolocate said feed-bar in either of two vertically spaced positions and totransmit vertical movements to said feed-bar in either of saidpositions, means including a manually actuatable crankshaft and aconnection from said crank-shaft to said link for shifting said link tocause the stud to be disengaged from one of said seats and engaged withthe other, and friction detent means acting on said link impositively tohold it in its two positions of adjustment.

4. In a sewing machine having a frame, a feed-advance rocker, afeed-lift rock-shaft, a feed-bar pivotally connected to said feed-ad-Vance rocker, an arm on said feed-lift rock-shaft, a stud carried bysaid arm, a feed-bar lifting link connecting said arm and said feed-bar,said link having a pair of vertically spaced seats adapted selectivelyto receive said stud to locate said feed-bar in either of two verticallyspaced positions and to transmit vertical movements to said feed-bar ineither of said positions, a crankshaft journaled in said frame, ahand-grasp on one end of said crank-shaft, a crank-arm on the other endthereof, and a link connecting said crank-arm with said feed-bar liftinglink, whereby manual turning of said crank-shaft shifts said feed-barlifting link to cause said stud to be disengaged from one of said seatsand engaged with the other of said seats.

5. In a sewing machine having a frame, a feed-advance rocker, afeed-lift rock-shaft, a feed-bar pivotally connected to said feed-ad-Vance rocker, an arm on said feed-lift rockshaft, a stud carried by saidarm, a feed-bar lifting link connecting said arm and said feedbar, saidlink having a pair of detent notches and a pair of vertically spacedseats adapted selectively to receive said stud to locate said feedbar ineither of two vertically spaced positions and to transmit verticalmovements to said feedbar in either of said positions, a second linkarranged adjacent to and parallel with said feedbar lifting link andpivotally connected to said feed-bar coaxial with the pivot of the firstnamed link, a crank-shaft journaled in said frame, a hand-grasp on oneend of said crank-shaft, a crank-arm on the other end of saidcrank-shaft, a link connecting said crank-arm with said feedbar liftinglink, whereby turning of said crankshaft shifts said feed-bar liftinglink to cause said stud to be disengaged from one of said seats andengaged with the other of said seats, and a spring detent carried bysaid second link and adapted to engage the notches in said feed-barlifting link yieldingly to hold the latter in its various positions ofadjustment.

6. A feeding mechanism for a sewing machine having a work-supportprovided with feed-slots, comprising a vertically movable andhorizontally reciprooable feed-bar, a feeddog carried by said feed-bar,means to give to said feed-bar endwise reciprocations, a rock-shaft, alaterally projecting stud carried by said rock-arm, a verticallydisposed link havrock-shaft, an arm on said ing its upper end pivotallyconnected to said 55 feed-bar, the lower end of said link being providedwith vertically and horizontally spaced seats adapted to receive saidstud thereby to hold said feed-bar in either of two vertical positions,in one of which said feed-dog operates through said feed-slots, and inthe other of which it operates below the upper surface of saidworksupport, and manually operated means to shift said link laterally tocause said stud to engage first one and then the other of said seats.

7. In a sewing machine having a frame including a throat-plate providedwith feed-slots, work-feeding mechanism including a feed-bar, a feed-dogsecured to said feed-bar and having teeth normally operating throughsaid feed-slots, m an for iving to said feed-bar endwise reciprocations,a feed-lift rock-shaft, a feed-lift rockarm carried by said rock-shaft,a stud carried by said rock-arm, a pair of parallel links connectingsaid rock-arm and said feed-bar for transmitting vertical movements tothe latter, one of said links being s-hiftable and having a pair ofvertically and horizontally spaced seats adapted to rest upon said studto determine the elevation of said feed-bar, spring means urging saidfeed-bar and links downwardly to maintain one of said seats in pressurecontact with said stud, manually operable means for shifting saidshiftable link to position the other of said seats beneath said stud tochange the elevation of said feed-bar, and a spring detent carried byone of said links and engaging the other link to hold the shiftable linkin its adjusted position.

8. In feeding mechanism for sewing machines, a feed-advance rock-shaft,a feed-lift rock-shaft, a feed-bar connected at one end to saidfeedadvance rock-shaft, a feed-dog carried by said feed-bar, a feed-liftarm fixed to said feed-lift rock-shaft, a pair of vertically disposedlinks pivoted at their upper ends to said feed-bar, a first one of saidlinks being provided in its lower end portion with an aperture and asecond one of said links being provided with a plurality of verticallyand horizontally spaced seats aligned with said aperture, a stud carriedby said feedlift rock-arm and projecting therefrom and entering theaperture in said first link, said stud also engaging one of said seatsin said second link, means to turn said second link about its pivot tovertical alignment with said stud and to move the other seat intovertical alignment with the stud, and spring means urging said feed-barand links downwardly to place the other of said seats in contact withsaid stud.

ROBERT SCI-IUL'IHESS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,417,865 Smith May 30, 19221,908,292 Grieb May 9, 1933 FOREIGN PATENTS Number Country Date 246,704Germany May '7, 1912 remove said one of said seats out of

